Terminal nanners, normal and sterile?

So I was reading some journal article on hormonal influences on florette development in cannabis (not related), and there was a section where it talked about how bud structures terminate, and it said in no uncertain terms that the florette either doesn't terminate (most sativas), terminates in a sterile (pistil-less) calyx (most indicas), or terminates in a nanner (stamen) (some hybrids).

Now the interesting part of that was that terminal calyxes are sterile in all cases (I guess in the strains they looked at), the strong implication is that terminal stamen (nanners) are also sterile, (and completely normal).

I was just wondering if anyone had more information or thoughts on the matter. I have tried to polinate plants with nanners before and it has always failed. It would be interesting to know if terminal (non-stress) nanners are actually sterile.

It does see, a5 least in my garden, that late nanners generally don’t have any effect andvery well may be sterile. By late I mean after 50 days.